Why bother using a product from a company that is notorious for failing to commit to most of their services, when you can run something which produces output that is pretty close (and maybe better) and is free to run and change and train?
This makes the image much more usable without editing.
If you're just generating something for fun then DallE/MJ is probably sufficient, but if you're doing a project that requires specific details/style/consistency you're going to need way more tools. With SD/A*1111 you can use a specific model (one that generates images with an Anime style for instance), use a ControlNet model for a specific pose, generate hundreds of potential images (without having to pay for each), use other tools like img2img/inpaint to hone your vision using the images you like, and if you're looking for a specific effect (like a gif for instance), you can use the many extensions created by the community to make it happen.